DE202006020330U1 - Device for exhaust air purification - Google Patents

Abstract

Facility for the thermal treatment of exhaust air (exhaust air purification) from mechanical-biological residual waste treatment and composting plants or industrial plants and laboratories, thereby characterized in that with chemical and / or biological pollutants loaded exhaust air (4) from the individual operating areas via a Conduit or duct system made of metal or for transport with chemical and biological contaminants of contaminated air Materials with differently shaped cross-sections, by means of compressors is sucked and this the reactor (7) of a fluidized bed combustion plant by overpressure over Line system the inert bed 7.1 consisting of quartz sand or other as fluidized bed suitable materials, as combustion or Vortex air is fed below the freeboard (7.2) via openings or nozzles and here is subjected to a thermal treatment.

Description

object The invention relates to a device for the thermal treatment of Exhaust air in mechanical-biological waste treatment and composting plants (hereinafter referred to as MBA) or industrial plants and laboratories.

inert gases and exhaust air from an MBA can in principle either over a biofilter or thermally treated.

The Limits of the 30th Ordinance to Implement the Federal Immission Control Act of 03.01.2001 (30.BImSchV) be respected. With lower local requirements - in particular abroad, biofilters are used.

At high demands of approximately 20,000 m ³ / h of MBA exhaust air, the so-called regenerative thermal oxidation technique (referred to below as RTO) is used, in particular in the Federal Republic of Germany. These systems burn trace and odorous substances with a supporting gas at temperatures of 850-1000 ° C.

There the mechanical-biological waste treatment in the FRG also in the future beside the waste incineration was to be used in waste management, the legal Frame adapted to the state of the art.

In the Regulation on the environmentally friendly Disposal of municipal waste and over biological waste treatment plants will be both the environmentally sound deposit of municipal waste (Deposition Ordinance AbfAblV) as well as the emissions limited from MBA (30th BImSchV).

For approval of MBA are on the part of the Federal Environment Ministry in the 30th BimSchV u. a. strict requirements for exhaust air emissions via the parameters Total Corg. and nitrous oxide as concentration and freight / Mg waste input. The 30th BimSchV provides for MBA comparable sharp requirements as the 17th BimSchV for waste incineration plants, the odor threshold even higher Conditions.

The The new version of the TA Luft, which has been in force since July 24, 2002, limits emissions from plant variants for non-thermal waste treatment, the not subject to the above-mentioned regulations. These include, for example purely mechanical treatment plants.

The Exhaust air purification at MBA was limited until 2001 mostly on the use of the combination scrubber and biofilter. Herewith can the new requirements are not met. (Doedens / Cuhls, 2000). The limits of the 30th BimSchV for Ges.-Corg. Can under consideration the emission situation with biofilters at MBA alone with regard to Methane concentrations and loads are guaranteed only with thermal means become. Main building block and state of the art in exhaust air treatment At MBA is thus the regenerative thermal oxidation. Known Procedures are the Vocsi Box from the company Hanse. It is a flameless one regenerative thermal oxidation plant for lean gas treatment, which is also for the MBA exhaust treatment is suitable. One differentiates the thermally recuperative oxidation, thermal regenerative oxidation and the thermally catalytic oxidation.

To the most effective cleaning equipment for exhaust air streams with organic pollutant loads counts the thermal afterburning.

basis The different post-combustion equipment is the oxidation from hydrocarbons to carbon dioxide and water. Of all exhaust air purification devices for hydrocarbon polluted Exhaust air, thermal afterburning plants have the best separation efficiency and can so even the most stringent limits. Three different ones Afterburner facilities are available from which quite individual and tailor made be selected on the application case the most effective can.

Thermally recuperative oxidation - thermal afterburning plants with recuperative exhaust air preheating (TNV)

The TNV systems are preferred for cleaning exhaust air with high Pollutant concentrations used. This arises mainly in the Printing, coating, laminating and impregnating.

TNV plants are largely insensitive to aerosol Abluftinhaltsstoffen and Variations in pollutant concentration.

The Oxidation of organic pollutants takes place at a combustion chamber temperature of about 750 ° C instead of. For optimum energy utilization, the heat energy the hot ones Used clean gas to preheat the pollutant-laden exhaust air. this happens in an internal shell and tube heat exchanger. This heat recovery can be of up to 76%. In order to increase the profitability further, additional Heat recovery systems for the production of thermal oil, Steam, hot water or hot air can be connected downstream.

Thermal Regenerative Oxidation - Thermal Afterburning Plants with regenerative exhaust air preheating (RNV)

The RNV systems with two, three or more heat storage beds become the Exhaust air purification used in the entire solvent processing industry. The systems work even at low pollutant concentrations and without downstream heat recovery very economical and will be for used a wide range of pollutant concentrations.

The exhaust air preheating takes place in ceramic heat storage beds. Through the mutual flow through the heat storage beds with hot clean gas and cold exhaust air up to 97% of the heat energy is kept in the system. The heat energy is generated by the auxiliary burner and the exothermic oxidation of the pollutants. Depending on the pollutant, RNV systems can work autothermally as low as 1.5 g / Nm ³ pollutant concentration. So that it does not come to the emergence of unpurified exhaust air when switching the flow direction, a buffer system or a third heat storage bed can be installed.

Thermal catalytic oxidation - Thermal catalytic afterburning plants (KNV)

The KNV systems are used to clean exhaust air with low or medium Pollution pollution, for example, from printing, the chemical and pharmaceutical industry as well as painting and coating plants of all kinds used.

In The KNV plants are subject to the oxidation of pollutants on a catalyst at temperatures of 200 ° to 450 ° C. These comparatively low temperatures are due to the participation of one Catalyst on the oxidation possible. The suitable mixed oxide or noble metal catalyst will accordingly the pollutants contained in the exhaust air selected. Due to the internal exhaust air preheating in a highly efficient plate heat exchanger be up to 85% of the heat energy of the hot Clean gas kept in the system. Because of the thereafter only small Pure temperature can KNV systems without secondary Heat recovery work economically.

The mentioned Thermal exhaust air purification systems are used in the MBA plant engineering.

Of the Disadvantage of these three devices is that for the oxidation of a so-called supporting gas needed as an energy source becomes. At today's energy prices this is a big disadvantage.

One Another disadvantage is that these facilities are very sensitive react on silicon deposits.

Of the in protection claim 1 specified invention is based on the problem a device for the thermal treatment of exhaust air in mechanical biological waste treatment and composting plants as well as industrial plants and to create laboratories that have described the negative ones Eliminated effects.

to Elimination of the negative effects described pursues the invention the goal, a simple, robust, cost and energy saving device to create, with a continuous exhaust air purification in particular for MBA Facilities, is achieved.

The Device consists in a thermal afterburning a Fluidised bed furnace (WSFA) the thermal oxidation of takes over in the exhaust air contained contaminants. The WSFA has, over others Facilities have the advantage that the exhaust air in the combustion chamber relative lingers for a long time. Thus, the device comes with lower temperatures than other incinerators. As an energy source for the oxidation are next to gases and liquid and solid fuels suitable without additional technical effort. you Can be applied to renewable fuels such as straw, rapeseed oil, waste wood and resort to high caloric waste to reduce energy costs. The fluidized bed replaced in this Process the ceramic bed as a heat storage. It consists of a quartz sand bed and is therefore much cheaper as the ceramic bed in the three-chamber process and insensitive to silicon deposits. Fluidized bed combustion systems are state of the art. There is to Example waste incineration plants, Landfill gas incineration plants, coal-fired power plants or sewage sludge incineration plants who work according to this procedure.

The Connection with an exhaust air purification system and the two-stage Combustion in which the cyclone is considered the 2nd oxidation stage for weak polluted exhaust air is used is a technical novelty. A significant advantage of the two-stage oxidation is the separate Combustion of different air contaminations.

The following embodiment shows in a flow chart 1 the operation of the invention.

The heart of the plant is the fluidized bed furnace WSFA ( 7 ) with the inert bed ( 7.1 ) (First Thermal Treatment Level).

The WSFA can be fixed ( 1 ) and liquid ( 1 ) as well as gaseous ( 6 ) Fuels are operated. To eliminate pollutants, in addition to the high temperature, it is possible to use additives ( 2 ). The highly polluted exhaust air ( 4 ) from the rotting halls passes through the exhaust air preheater ( 9 ) in the inert bed ( 7.1 ) of the WSFA ( 7 ) (First Thermal Treatment Level). Here the highly loaded air is thermally cleaned.

The ash ( 14 ) is passed over the cyclone ( 8th ) separately. The cyclone is used in this facility for the residual heat exchanger ( 13 ) in the fireplace ( 15 ) heated, low-loaded, untreated exhaust air ( 3 ) from the other buildings, at the same time as an oxidation chamber (Second Thermal Treatment Level) used. The two thermally cleaned air streams then enter the common manifold ( 12 ) in the air preheater ( 9 ). They pass part of the entrained heat energy to the highly polluted exhaust air. Afterwards, the purified air enters the heat exchanger ( 10 ).

Here become either the gaseous, liquid or solid fuels preheated or external heat issued. Then the cleaned exhaust air enters the chimney.

These Facility has opposite other facilities have the advantage that due to the characteristics the WSFA, the exhaust air does not need to be pretreated. (Deacidification and Biofilter). The process is insensitive to silicon deposits.

The Inlet temperature is over other Facilities only 850 ° C. Due to the fluidized bed creates a long residence time of the to be cleaned highly loaded exhaust air.

The Device has two thermal treatment stages. Therefore has one the possibility the slightly polluted exhaust air with an inlet temperature of only approx. 450-700 ° C thermal to treat.

in the Cyclone, the second thermal treatment stage, takes an ideal Mixing of the two exhaust air streams. Here takes over the approx. 700 ° C warm exhaust air from the WSFA, the thermal treatment of the low contaminated exhaust air. That saves energy. With the preheating of the Air and fuel flows by means of preheater and residual heat exchanger Almost all energy remains in circulation.

1

supply of solid and liquid fuels

2

supply of additives

3

low contaminated exhaust air

4

heavily loaded exhaust

5

cleaned exhaust

6

fuel gas (Support fire)

7

fluidized bed combustion WSFA (First Thermal Treatment Level)

7.1

Enertbett WSFA

7.2

freeboard

8th

cyclone (Second Thermal Treatment Level)

8.1

combustion chamber

9

Preheater for the heavily loaded, untreated exhaust air

10

Preheater for the liquid, gaseous and solid fuels as well as external heat

11

management for thermal treated exhaust air to the cyclone

12

manifold thermally treated exhaust air from the second thermal treatment stage

13

Residual heat exchanger for the preheating the slightly polluted exhaust air

14

ash

15

fireplace

16

bypass line

Claims (4)

Device for the thermal treatment of exhaust air (waste air purification) from mechanical-biological Restabfallaufbereitungs- and composting or industrial plants and laboratories, characterized in that the loaded with chemical and / or biological pollutants exhaust air ( 4 ) is extracted from the individual operating areas by means of a conduit or channel system made of metal or of materials suitable for transporting with chemical and biological contaminants contaminated air with differently shaped cross-sections, by means of compressor and this the reactor ( 7 ) a fluidized bed combustion plant by means of overpressure via a conduit system the inert bed 7.1 consisting of quartz sand or other materials suitable as a fluidized bed, as combustion or fluidizing air underneath the freeboard ( 7.2 ) is supplied via openings or nozzles and subjected here to a thermal treatment. Device for the thermal treatment of exhaust air (waste air purification) from mechanical biological waste treatment and composting plants or industrial plants and laboratories, according to the preceding claim, characterized in that the exhaust air ( 3 ) and ( 4 ) from different areas such as the area of the rotting chamber ( 4 ) and the freely accessible area chen ( 3 ) a mechanical-biological Restabfallaufbereitungs- and composting system is thereby extracted with different chemically and / or biologically contaminated exhaust air via two separate line or duct systems by means of compressor and the exhaust air ( 3 ) the combustion chamber ( 8.1 ) in the cyclone ( 8th ) or the exhaust pipe ( 11 ) is supplied via openings or nozzles by means of overpressure whereby these (exhaust air ( 3 )) with the via the fluidized bed reactor ( 7 ) thermally treated exhaust air ( 4 ) and via the exhaust pipe ( 11 ) the combustion chamber ( 8.1 ) is guided together via openings and nozzles and by mixing with the hot exhaust air ( 4 ) is subjected to a thermal afterburning. Device for the thermal treatment of exhaust air (waste air purification) from mechanical biological waste treatment and composting plants or industrial plants and laboratories, according to the preceding claim, characterized in that the exhaust air ( 3 ) and or ( 4 ) is extracted from the same or from different investment areas together via a line system by means of compressor and the exhaust air is then divided into two exhaust air streams via two duct or duct systems wherein an exhaust air flow to the combustion chamber ( 8.1 ) in the cyclone ( 8th ) or the exhaust pipe ( 11 ) is supplied via openings or nozzles by means of overpressure, whereupon this exhaust air stream with the via the fluidized bed reactor ( 7 ) thermally treated second exhaust air stream via the exhaust pipe ( 11 ) the combustion chamber ( 8.1 ) is brought together via openings and nozzles and is subjected by the mixing with the hot exhaust air of a thermal afterburning. Device for the thermal treatment of exhaust air (waste air purification) from mechanical-biological Restabfallaufbereitungs- and composting or industrial equipment and laboratories, according to the preceding claims, characterized in that in the combustion chamber ( 8.1 ) of the cyclone ( 8th ) or the exhaust pipe ( 11 ) a burner for emergency and repair operation is located.